When inspecting the endface of a fiber-optic connector with a fiber inspection probe or when measuring the optical power at the output of a fiber-optic connector or any other fiber-optic termination with an optical power meter, the tested fiber-optic termination needs to be temporarily mated with the test instrument in proper optical alignment therewith. However, the tested fiber-optic termination generally does not need to be firmly attached to the test instrument (as it would be with a screw-threaded mechanism for example). Ideally, for efficiency of the testing operations, the connection and release should be made with the fewest possible manipulations.
A common solution to provide a quickly releasable mechanical connection between a ferrule connector under test and a fiber inspection probe is provided by employing a split ceramic sleeve enclosed within a tubular body. The diameter of the split sleeve is nominally slightly smaller than the diameter of the ferrule. When mating the connector, the split sleeve opens up slightly to accommodate as a connector ferrule is inserted therein. On account of its Young's modulus, the split sleeve exerts a transverse force on the ferrule, this force providing a small retention force so that the connector does not inadvertently detach from the fiber inspection probe during inspection. An operator can still easily disconnect the connector from the test instrument by simply pulling it out of the split sleeve.
Other solutions that exist employ a metal tip having a small hook (e.g. made of stainless steel) that expands to receive a connector ferrule therein. In reaction to deformation of the metal when the connector ferrule is inserted, a transverse force is exerted by the hook on the ferrule, which retains the connector ferrule on the fiber inspection probe.
A problem with the above-mentioned methods is that they are typically unduly fragile. In the case of the split ceramic sleeve, the sleeve often ruptures on mechanical impact or with use. In the case of the metal tip, it is very susceptible of being distorted by a mechanical impact, rendering it non-functional. Manufacturing of such tips is also difficult and therefore expensive.
There is therefore a need for a low cost and more robust system for temporarily mating and retaining fiber-optic terminations to test instruments, which also may be easily released.